IPv6 trough openVPN.

Hi,
I have a working IPv6 tunnel from HE (Hurricane Electric) and a working openVPN server on my linksys e2000 withe tomato Tomato Firmware v1.28.7503 MIPSR2Toastman-RT K26 VPN.
My kids can make the openVPN connection and go to the Internet, no problems.
But the connection is IPv4 onlie is there a way to advertise IPv6 to the openVPN clients to ?
Or is it IPv4 onlie ?